Difference between Hardwired and Micro programmed control unit

Last Updated on by Sumi

Hardwired control unit:

  • It is a unit that uses combinational logic units featuring a finite number of gates that can generate specific results, based on instructions that were used to invoke those responses.
  • The speed of the operation is fast.
  • Here, for the modification, the entire unit should be redesigned.
  • They are more costly to implement.
  • It is difficult to handle complex instructions.
  • It is difficult to perform information Decoding.
  • They use a small instruction set.
  • There is no control memory usage.
  • They are used in processors that use a simple instruction set known as the reduced instruction set computers(RISC).
  • They are not flexible.
  • Here, the sequential circuit is used.
  • Here, The designing process is complicated.

Micro programmed control unit:

  • It is a unit that contains microinstructions in the control memory to produce control signals.
  • The speed of operation is slow because it requires frequent memory access.
  • Here, modifications can be implemented by changing the microinstructions in the control memory.
  • They are less costly to implement.
  • It is easier to handle complex instructions.
  • It is less difficult to perform information Decoding.
  • They use a large instruction set.
  • They use control memory.
  • They are used in processors based on complex instructions set known as complex instruction set computers(CISC).
  • They are flexible.
  • Here, a programming circuit is used.
  • Here, The designing process is systematic.

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